1. Field of Invention
This invention relates to an angle detecting apparatus for detecting the rotational angle of an axis using a short pulse signal.
2. Description of the Related Art
A conventional angle detecting apparatus, such as a rotary encoder, provides a dial or a precisely graded scale onto a disc. The dial is then optically or electro-magnetically read to detect the angular position of the disc.
The dial must be graduated precisely to ensure accurate angle detection. High precision sensors are required for reading the minute markings on the dial. Such sensors are generally expensive because of their complicated structures and their precision is easily affected by the environment or shocks. An inexpensive and reliable angle detecting apparatus having a simple structure has been desired in many fields.